Alex Karev on the hit medical drama Grey's Anatomy started out as a polarizing character, but he went on to become of the most beloved characters in the show's long history. Alex was insolent and arrogant when he was first introduced as sort of a foil to the gentle George O'Malley, but in time, he became softer and mellower, and of course, Meredith's most trusted friend and lieutenant.

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Alex had a gruff exterior, but underneath that there lay a caring friend, lover, and medical professional. From going out of his way to comfort and save his patients to helping save Meredith's career and looking out for Jo in his own way, Alex had some extremely nice, heartwarming, and iconic moments on the show.

When He Flew Back From His Boards To Save A Patient

Alex holding a baby in NICU on Grey's Anatomy.

Alex did a rather wonderful thing during his oral boards in Los Angeles. He flew all the way back to Seattle when he realized they could still try some other means to save little Tommy, who was on life support in the NICU.

He was well aware of how crucial the day was for him, and he would have had to wait an entire year if he hadn't made it to the exam venue at least for the second session. However, he still took the risk and flew back, prioritizing the life of his patient over his own selfish interests.

When He Performed The Kangaroo Hold For A "Tiny Human"

Alex doing kangaroo hold for baby in NICU Greys

Alex had one of his most iconic moments in the episode, "Invest In Love," when he performed the kangaroo hold for a prematurely born baby, or what Arizona Robbins would call "a tiny human." In the kangaroo hold, a baby is given direct skin-to-skin contact with the parent to help it stabilize.

Alex performed this for a baby whose mom, Laura, had been in an accident and was too sick to take care of her child. He started speaking to the child very soothingly, which caused her vitals to improve a bit. Bailey then got him to take his shirt off and do the kangaroo hold, and after several hours of holding the baby, its vitals indeed improved by leaps and bounds. This incident also proved that Alex had a true penchant for pediatrics.

When He Looked After His Family

Alex holding his mom's hands and looking into her eye in Grey's Anatomy.

As a young boy, Alex took care of his mother who has schizophrenia. He had even trained in wrestling to save his mom from his abusive father, which was genuinely sweet of him.

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He also stole food once to feed his young brother and sister, which goes to show that underneath his gruffness, Alex is very caring, even as a young man. Even later, it was revealed that he regularly sent money to his mother as an adult to make sure she lived comfortably.

When He Took Care Of Ava

Alex comforts Ava at the hospital

Alex was ready to tend to Ava for as long as she needed, although when he found out she was married, he did the right thing and stepped back. Then Ava came back thinking she was pregnant. Although it was revealed that she was suffering from stress and hadn't been pregnant after all, Alex was more gentle and loving with her than he was ever shown to be until that point.

He brought her to Meredith's place to look after her, feeding her and cleaning up after her. He opened up to her about his own family and was ready to commit to her when he thought she was carrying his child. The entire affair with Ava showed Alex in a decent, mature light.

When He Gave Up His Johns Hopkins Offer

Alex And Arizona in Greys Anatomy

Alex was offered a pediatric surgery fellowship at the prestigious Johns Hopkins, but it was during that time that the chopper carrying a bunch of doctors from Seattle Grace to Boise went down in the middle of nowhere in the shocking season 8 finale.

Alex kept postponing leaving for Johns Hopkins, as he considered it his duty to hold the reigns of the peds department since Arizona was still recovering from the trauma and eventually had to have her leg amputated. Alex finally gave up the offer altogether to stay back at Seattle Grace.

When He Was There For Meredith

Alex hugging Meredith after her assault Grey's Anatomy

Alex Karev was one of the only original interns besides Meredith who stayed on the longest. Fans know that he became Meredith's "person" after Cristina Yang's departure.

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Alex's bond with Meredith increased even more after Derek's untimely death. The two shared an easy camaraderie, their friendship going back years. Alex's genuine love for Meredith was captured especially beautifully after she was attacked by the patient in "Sound Of Silence."

When He Surrendered Himself To The Police

Alex telling Meredith about beating DeLuca

After Alex beat DeLuca up without even waiting to find out what he was doing with Jo in her room, he knew he had to do the decent thing and gave himself up to the police.

The Alex Karev of the earlier seasons might have thought twice before surrendering, but the Karev of season 13 didn't back down or try to escape the law. On the contrary, he was ready to take a plea deal, also protecting Jo in the process, as she might have been dragged into the mess if the status of her marriage to the deplorable Paul somehow came to light.

When He Comforted Izzie After Denny's Death

Alex Karev (Justin Chambers) comforting a sobbing Izzie Stevens (Katherine Heigl) after Denny (Jeffrey Dean Morgan) died in Grey's Anatomy.

Alex was shown comforting Izzie when she broke down after Denny Duquette's tragic death. As Izzie lay weeping and holding Denny's body, unable to believe what had happened, it was Alex who came and carried her out of the room in his arms.

Alex's relationship with Izzie was a fan favorite arc, despite being fraught with tension. Yet there were moments when he was both gentle and supportive to Izzie Stevens, and although jealous of Denny while he was alive, he tried to be understanding of her grief once he passed.

When He Was A Good Friend To Little Lily

Lily breathing into a tube in Grey's Anatomy.

Alex had a natural connection with kids, so in spite of his abrupt departure, it actually makes sense that he would leave to be with his own children. With the patient Lily, he was gentle, sweet, and caring to the extent that Lily became a huge fan of Dr. Karev.

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Alex would practically live in the hospital focusing all his energies on taking care of Lily and tending to the new trachea he and Arizona were growing naturally for her from her own cells. Alex even sang for Lily, very badly but adorably nonetheless, to soothe her nerves while she was inside the MRI machine since she couldn't take her iPod with her inside the machine. This was yet another time patients knew that Alex Karev was made for pediatrics, in spite of his self-proclaimed lack of interest in kids.

When He Rounded Up Meredith's Patients

Alex in court room in Grey's Anatomy

Meredith Grey nearly lost her medical license when she was caught for insurance fraud, which she had committed to help a patient and her father. Her colleagues stood steadfastly by her side at the time, but it was her "person," Alex, whose efforts finally paid off.

Alex had rounded up as many patients of Meredith as he could, whose lives Meredith had saved over the years and who were deeply indebted to her. It was also Alex who had got in touch with former colleagues of his and Meredith's, such as Cristina Yang, Izzie Stevens, Callie Torres, April Kepner, and Arizona Robbins, all of who had sent in raving testimonials about Meredith as a doctor. It was this stunt of his that eventually got Meredith off the hook - a sweet gesture if ever there was one.

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