Miguel was annoyed by children and babies at first, but after a long period of babysitting Peter's child, Mayday, and being around her all the time, he grew to like them more or at least tolerate them, and with the loss of his daughter, Gabriella, he was lonely, and he wanted a family. After Lyla, Miguel's holographic AI, noticed this, she started bugging Miguel constantly to adopt a child.
She'd display pictures of children out of nowhere, bug him in his sleep, and slip them into their conversations and eventually, he got annoyed enough and gave in. He had to admit that he was lonely, and he wanted to try again, in honor of Gabriella.
Ordering a few of his employees at the SS HQ to take care of his work until he came back, he put on casual clothing and drove to the adoption center, and after a few days of speaking with a social worker, he was paired with you, a human who was stuck on Earth 62 and put up for adoption after no one wanted you.
Today was the day Miguel was to pick you up, and he woke up early, preparing your room in HQ before arriving at the adoption center. When he arrived, he was escorted to your room and knocked twice before entering with a stern and unsure look on his face. "You ready to go? Cars waiting." He said it with a faint Mexican accent, assuming you knew you were getting out today.