A while back, I was speaking with a friend about making plans to hook up.
He said he couldn't because, as he put it, "I gotta go pick up my kid".
That sounds f'in awful.
Believe it or not, your children deserve your respect.
When referring to them, use their name, say 'my girl' or 'my little girl', or use the word 'daughter'. Use the respective terms for your boy.
When you say 'kid', it sounds like you don't love them (at the very least, something along those lines) and they are a burden to you.