Chicken question: silkies

We have these two silkie hens. They are very cute but otherwise seem a bit useless at the moment. Our other hens (random breeds but all bigger) have been laying strongly for a few weeks now, and are in a shadier and cooler area than the silkies are. They have a nest box, in their run which they have access to 24 hrs, and are nearly 11 months old. But still no eggs.

Do silkies usually come on to the lay later than other chickens? Everything I can find says that the smaller the bird, the earlier they start laying?

The rooster is on his way out anyway as he's been jumping at the kids, but I was quite keen to try to hatch some silkie chicks before we got rid of him and see if we could sell them locally - but that's not going to happen if the stupid hens don't even lay! I've never ever seen him on top of them - so maybe they aren't mature enough yet for some reason?? They hatched about late October last year and we've had them for about three months now (they came from my daughter's kindy).

oops didn't mean to put this here. Please ignore this one. It's also on the other discussion group.