Jessica Simpson‘s family can’t wait for her to get home!

The singer and fashion mogul, 39, jetted off to New York City for work this week — her first trip without her 6-month-old daughterBirdie Mae— but her husbandEric Johnsonand two older kids (sonAce Knute, 6, and daughterMaxwell “Maxi” Drew, 7) have everything under control.

“Hey, let’s say hi to Mama,” former NFL player Johnson, 40, tells his children in a cute selfie-style home video taken while the foursome hang out in a pool. Birdie is dressed in a colorful rash-guard swimsuit and blue bucket hat as her dad holds her, while her two big siblings splash around in the background.

“I love you more!” the two older kids adorably yell over each other, leading Johnson to laugh before the end of the clip — which Simpson captioned, “Meanwhile, back at home 😭.”

Jessica Simpson/ Instagram; David Livingston/Getty

Jessica Simpson’s family

Simpson revealed on Instagram Tuesday that she was “emotional for many reasons” as she headed off on her first trip away from daughter Birdie, whom she and Johnson welcomed on March 19.

But she was also “so proud to feel like [herself] again,” sharing that she hadlost 100 lbs. since giving birthand had previously “tipped the scales at 240.”

Jessica Simpson and daughter Birdie.Jessica Simpson/Instagram

Jessica Simpson

“Even when it felt impossible, I chose to work harder. 💚,” Simpson noted proudly, captioning atwo-photo galleryin which she wore a black midi dress featuring long bell sleeves, a pleated skirt and a belted, cinched waist.

“She’s working hard and working out and eating healthy and trying to get back in her best shape and excited for what’s ahead,” a source told PEOPLE of the star, whose upcomingmemoir is set to be releasedon Feb. 4.

RELATED VIDEO:Jessica SimpsonShares Adorable New Photos of 4-Week-Old Birdie with Daughter Maxwell and Son Ace

“She’s trying to get back to her healthiest place,” the insider continued. “And she just wanted to get to a place where she feels her healthiest. She’s not focused on the number, but on feeling her best self.”

“Jessica had a trainer [Harley Pasternak] and she was very committed to working out. She also did a lot of walking — walking is huge for her mentally and physically,” the insider said. “It’s alwaysbeen something she does toclear her head and for the steps.”

“She ate a lot of vegetables,” the source continued. “She also discovered the vegetables she likes that can also be masked into different dishes. And she limited foods that were fried and high in calories. But she did not deny herself, and gave herself nice healthy meals. She believes in moderationand she was conscious of her goal. At certain times, she allowed herself to indulge.”

source: people.com