Ashton and Demi unsure over kids

At one time it did look like Ashton Kutcher, 26, and Demi Moore, 41, were definitely heading for the altar, despite their age difference. So what happened?

“Kids are a huge issue,” says an inside source, according to the National Enquirer. Kutcher loves Moore’s three daughters (from ex-hubby Bruce Willis), but he would like some of his own one day.

“It’s the main reason he hasn’t proposed yet,” says the source. “Demi doesn’t know if she wants to have more kids.

“He gravitated to Demi because of her kids. A house, a family – that’s what he wanted when he moved to LA,” added the souce. The insider wasn’t sure whether the relationship can last if the issue of children wasn’t resolved.