The 35-year-old new mother rocked a pair of brown overalls and white sandals, as she cradled six-moth-old daughter Louetta in a cheetah baby carrier.
She was also joined by boyfriend Derek Thomas, 29, who sported a white t-shirt, black jeans and Crocs clogs.
Rumer — who recently suffered from the flu alongside her daughter — wore her bleach blonde tresses in a messy bun.
The star accessorized with a pair of earrings and appeared to be makeup-free on the errand run.
Casual look: Rumer Willis, 35, stayed comfortable while grabbing groceries with her six-moth-old daughter Louetta and boyfriend Derek Thomas, 29, in Los Angeles on Sunday
Comfortable: The new mother rocked a pair of brown overalls and white sandals, as she cradled in a cheetah baby carrier
Rumer — who’s the daughter of Hollywood icons Bruce Willis and Demi Moore —has been sharing about her journey as a first-time mother on her Instagram page with photos, videos, along with updates on hers and her babies health and wellness.
On Thursday, the actress and singer shared three new photos when she revealed how she and Louetta were both were stricken with the flu at the same time this past week.
In the lengthy new post she wrote about the lessons she learned while struggling with the idea about how she could take care for her child while she was sick.
‘I have been reflecting this week on the strength of Mamas, of this incredible gift of resilience and love. The softness that can come from vulnerability and asking for help,’ she began. ‘The flu took both my Lou and me simultaneously, and it brought not just symptoms but moments of doubt. Could I manage taking care of her and myself in this weakened state?’
After disclosing her self doubt and ‘storm of uncertainty’ about whether she could take care of herself and her daughter while sick and weak, the Once Upon A Time In Hollywood star revealed how they both ‘discovered an uncharted strength within ourselves.’
‘The resilience I summoned in the face of a common challenge mothers everywhere deal with truly showed me so much about myself and my capacity,’ she explained.
She continued, ‘As a parent, you sometimes question your abilities, but that week, as the flu raged on, it became clear that I was more capable than I ever thought. That I could be her safe place and I could hold the container for both of us.’
Willis, who appears to be breastfeeding baby Lou while relaxing in bed in the cover photo, went on to share her gratitude for ‘the moments that push me and challenge me and show me how much stronger I am than ever I thought I was.’
Health update: Earlier this week Willis gave an update on her and baby Louetta’s health, after they were both stricken with the flu at the same time
Look of love: She has been sharing about her journey as a first-time mother on her Instagram page with photos and videos
Growing family: Willis and boyfriend Derek welcomed their first child in an unmedicated home birth on April 18, five days after her estimated due date
Clapping back: Rumer recently blasted ‘a**hole’ online bullies for making ‘mean’ comments on an article about her
‘This past week magnified how challenging navigating some of the difficult moments that come up during the postpartum period especially without community and support.
Willis concluded, ‘That’s why I stand proudly with @Needed, advocating for better postpartum support, maternal health, and community.’
Willis and boyfriend Derek welcomed their first child together in what was an unmedicated home birth on April 18, five days after her estimated due date.
Her latest outing comes after the star recently clapped back at negative comments people left on a recent article about her, as she told trolls who called her a ‘nepo baby’ to not ‘be an a**hole.’
It was the second time in recent months that Rumer has faced online backlash.
In August the star clapped back after she was ‘shamed’ for posting a breastfeeding photo.