No.
Point 1. Once you get into the benefits system (which shows you're struggling, whether you're working or not, disabled or not, ill or not), then having more children while in that condition is selfish and irresponsible. Why make more when you're already struggling to cope? Children deserve much better than that and it starts with the parents, not the government.
Point 2. Perhaps, a bit of leeway for those who've already paid into the system but circumstances have led to claiming (more) benefits. All children at the time of claiming should be taken into consideration but no more after that (See point 1).
We can't have another wave of people choosing to pop out 5 kids in 6 years (4 of them on DLA, one after the other) while "struggling" on benefits (working or not). It really makes no sense.
(Edited to fix the numbers manually. It keeps automatically adding 1 to each).