"I didn't want it to be in photos, so I wore things that would cover it up. Now, more than ever, I feel confident in who I am and what I went through … and I'm proud of that.
"T – Congratulations on what you're doing for women, launching @lamariette whose message is just that … all bodies are beautiful."
Gomez models a $120 Selena one-piece that is part of her collaboration with La'Mariette, with co-founder Theresa Marie Migus being the "T" who she is praising in her caption.
The 28-year-old lupus sufferer received the organ donation from her friend Francesca Raisa in 2017.
"There aren't words to describe how I can possibly thank my beautiful friend Francia Raisa. She gave me the ultimate gift and sacrifice by donating her kidney to me. I am incredibly blessed. I love you so much sis. Lupus continues to be very misunderstood but progress is being made."
She made her diagnosis public in 2015 in an announcement to Billboard.
The star revealed how she had "been through chemotherapy" to try to treat the illness, which resulted in her stint in rehab at the Arizona Meadows.
After the transplant, Raisa spoke to Us Weekly about her life following the procedure.
Selena has shown her fans the scar in the past. Photo / Selena Gomez / Instagram
"It's harder as the donor because we are losing something our body didn't need to lose, so trying to recover from that, and she's gaining something her body needed. So she's up and at it immediately and I had a hard time.
"I couldn't take a shower by myself, I had to have someone help me because I couldn't move.
"I'm a very, very active person, so the fact that my doctor said I couldn't move for two months. Two months, I couldn't do anything active.
She continued: "All I could do was walk. That was very hard for me and I have a dog and every day the thing I look forward to is drinking my coffee and walking and I couldn't do that. It was really, really hard."
