Kim Kardashian's daughter North, 8, & niece Penelope, 9, help Jessica Simpson's kid Maxwell open gifts at 10th birthday

Jessica Simpson reveals daughter Maxwell is friends with Kim

Jessica Simpson & Kim Kardashian's Daughters Bond On Birthday Trip

Jessica Simpson, 42, shares a photo of her two eldest children

North West and Penelope Disick Celebrate Jessica Simpson's

Jessica Simpson's Daughter Maxwell Celebrates 10th Birthday with

Jessica Simpson's Daughter Maxwell Celebrates 10th Birthday with

North West and Penelope Disick celebrate Jessica Simpson's

Jessica Simpson reveals daughter Maxwell is friends with Kim

Kardashians Bring Kourtney's Daughter To Beyonce Concert: Photos

Jessica Simpson & Kim Kardashian's Daughters Bond On Birthday Trip