On Sunday Kourtney Kardashian headed to a birthday party in Los Feliz with Mason and baby Penelope, and it's a good thing both of her kiddies were on their best behavior, because she really had her hands full!

Earlier in the day Kourt tweeted, "Missing our Greece vacation!! So excited to relive the memories on tonight's #KUWTK episode..." This family never stops promoting themselves ... but does momager Kris Jenner have to remind everyone to tweet about their reality show or is that a chore for one of their many assistants?