Raph respects April. It’s pretty clear.
For example, he made it clear to Donnie that he made her uncomfortable in “A Foot too Big”. He knows her boundaries and knows how to treat her. Sure, there’s a few jokes here and there, but he never acted like she can’t do anything. He’s never really insulted her. And now, he sees her as part of the team.
Basically, I’m saying he respects her as a person and doesn’t see the need to try and baby her. He doesn’t really treat her as some weak, pitiful girl. There are times he says cocky stuff, but he never gets into her personal space like Casey or Donnie have.
There isn’t a whole lot of interaction between the two in the series, but from what I’ve seen, he’s not overly protective of her nor does he treat her like a baby.