LOS ANGELES - Pop star Madonna celebrated her adopted son David Banda's milestone 16th birthday with a sweet tribute and a backyard party.

In an Instagram post last Saturday (Sept 25), a day after his birthday, Madonna, 63, posted a series of photos of Banda, whom she had adopted when he was 13 months old with ex-husband, British director Guy Ritchie.

The mother of six wrote: "I cannot believe you have grown into this young man. This artist. This athlete. This articulate and charismatic human. Who knew when I met you at Home of Hope Orphanage in Malawi, drinking coke out of a baby bottle and wearing no diaper that you would become this force of nature?"

She also threw him a party in their backyard and posted photos of his birthday bash, which included colourful balloons around the pool, on Tuesday (Sept 28).

Banda, whose mother died of childbirth complications, had pneumonia and malaria when he was adopted.

Madonna's other children include Rocco Ritchie, 21, whom she shares with Ritchie; Lourdes Leon, 24, whom she shares with former partner Carlos Leon, a fitness trainer; Mercy, 15, who was adopted from Malawi in 2007; and twins Estere and Stella, nine, who were also adopted from Malawi in 2017.

Last month, Madonna celebrated turning 63 with the birthday wish that friends and fans would adopt a bed at Mercy James Centre hospital in Malawi so that sick or injured children can receive care in the African country.