Khloé Kardashian's Daughter True Is Obsessed With Her New Baby Brother: 'She Is Loving Being A Big Sister'

No sibling rivalry here! It's been just a few days since Khloé Kardashian and Tristan Thompson welcomed their second child together via surrogacy, but their 4-year-old daughter has already adapted to being a big sister!

"They are all truly ecstatic about welcoming a new baby," a source shared of the family. "True is old enough that she can really help out and be involved with feedings and diaper changes. She is loving being a big sister."

A second source said the toddler is eager to "be a 'mini mommy' to the baby."

The first insider added it's "a dream come true" for Kardashian, 38, to have another child, and she's thrilled to see that her firstborn isn't expressing any jealousy over the tot.

"She loves watching her and seeing her in this new role," the insider gushed. "She's in heaven with all of it and feels so blessed she was able to give True a sibling."

The Good American co-founder made that much clear, as after the little boy arrived, she posted a smiley photo of True alongside a flower arrangement, captioning it, "My happy sweet girl 💕."

Despite all the excitement and love, the mom-of-two has no intention of reconciling with Thompson, 31, who has cheated on her more than once. His most recent tryst came about last year, as he secretly fathered a child — Theo, now 8 months — with a woman named Maralee Nichols.

The NBA player didn't fess up to his infidelity until after the paternity test came back, but at that point, the surrogate he and Kardashian chose was already pregnant.

After the reality star found out about the other woman, she called it quits on their romance yet again, but as OK! previously shared, the Strong Looks Better Naked author is confident the basketball plater will be a present father.

"One positive she’s clung onto all along is that Tristan is a wonderful dad to True," the insider said. "Khloé has zero doubt he’ll step up and do the right thing with their new baby too."

Thompson also shares son Prince, 5, with ex Jordy Craig.