How big is my lap?

It is hard for a mom to carve out time for herself.  As I am typing right now, I have my daughter breastfeeding and my son sitting on the second half of my thighs and knees. My son is using my daughter's back to rest his back on.  I have two screens up on the desktop of my computer -- this screen (for me to write) and youtube (for my son to watch G scale trains).  I love being a stay at home -- these are the moments that I will not be able to recapture in the future. These moments pass too fast.  It is hard to get things done -- things that I want to do.  Anyway, I didn't think this moment should pass without me documenting it. How big is your lap?