Do you have sex when the kids are at home?

So I have 2 children, my son who's 6 and my daughter who's 2. Now my son is getting a little older and more aware, we're getting really wary about having sex when he's at home as he tends to wake up multiple times during the night and walks in our room. Every time a floorboard creaks we jump apart thinking he's up and about!!! Generally we only have sex when he's sleeping at his grandparents which is not very often. So was wondering what you guys do, do you still have sex when your kids are at home, how do you manage it? Last night we shoved a towel under the bedroom door so he couldn't open it!!! Desperate times called for desperate measures lol xx