First and Foremost, have I mentioned how absolutely adorable Milton is? If not, well I guess I just did. He looks so cuddly. I love the grump face when you first wake them up.. it's too much to get mad at!
As far as your liner question, my sewing skills are limited to what I can do by hand, and what I remember of doing a hem... so yeah, I abuse my friends with sewing machines
LOL. But maybe make a small square with some sort of batting in the middle and slip it where his favorite pee spot is.. make it like a wee pad and set that on top of the liner... I'm probably not explaining it well, or better yet, buy some pee pads and cut them into small squares for his favorite spot?