Per Shams Charania of The Athletic and Stadium on Wednesday, Cook will wear the No. 28 as a combination of Gigi's No. 2 and Kobe's No. 8.
"No. 2 is Gianna's number," Cook told Charania. "I feel it should be retired. It's hers."
After Kobe and Gigi Bryant were among nine people killed in a helicopter crash on Sunday, a number of NBA players have paid tribute to them by wearing his No. 8 or No. 24 on their jerseys or written messages on their sneakers for games.
Kobe's No. 8 and 24 jerseys were retired by the Lakers in December 2017. Gigi wore No. 2 on the basketball team coached by her father.
When Cook signed with the Lakers as a free agent in July, he took the No. 2 jersey and used it in the 30 games he's played for the team.