Jessica Simpson says having children has made her relationship ''stronger''.

The 33-year-old singer gave birth to son Ace Knute in June - her second child with fiancé Eric Johnson, with whom she also has 15-month-old daughter Maxwell - and she believes that parenthood has brought her even closer to the retired NFL player.

She said: ''My relationship with Eric has only grown stronger with the additions to our family. I love seeing him as a dad. I feel like I reached a new level of love for him and I didn't think I could love him any more than I did already. Becoming a parent is such a unique and profound experience and doing it together has brought us even closer.''

Jessica is grateful Eric, 33, is a hands-on dad with Ace and Maxwell and reveals that he doesn't shy away from changing nappies.

She added to the new UK issue of HELLO! magazine: ''Eric is incredible. I can safely say he has changed way more diapers than I have. Any time either of our babies needs anything, Eric is right there. I am so lucky to have him.''

It seems the couple's young daughter, Maxwell, has embraced her brother as well and regularly showers him with affection.

Jessica added: ''Maxwell is absolutely a daddy's girl. She and Eric have such a special relationship. We explained to her that she was going to have a brother while I was pregnant and she was so cute - she would kiss my belly and rub it. Even though she is probably too young to fully understand, she is already giving Ace so much love, holding him and hugging him.''