The good news keeps on coming! As if a big family wedding wasn't enough, the reality star and boyfriend Scott Disick will welcome their third child later this year. Already parents to son Mason, 4½, and daughter Penelope, 23 months, the couple are excited about expanding their brood. "Three kids is a lot to handle! But [Kourtney]'s happy – she's always wanted a big family with Scott," a source tells PEOPLE.