Step sister's jealousy intensifies after marriage and desire for more time together

My wife and I have been married for a few years now, and my step sister has been feeling left out ever since. She\'s always asking to come over and spend time with us, but we\'ve been pretty busy with work and other things. Lately, she\'s been getting more and more jealous of our relationship, and I think it\'s time to do something about it.