Barack Obama will fill in for Sen. Edward Kennedy in delivering the commencement address at Wesleyan University on Saturday.

Kennedy was to give the speech at the graduation of his step-daughter Caroline Raclin '08, who will be receiving her bachelor of arts degree at the ceremonies, but sidelined himself following release from the hospital earlier this week after being diagnosed with a malignant brain tumor.

Obama was endorsed by the Massachusetts Democrat earlier this year, and Kennedy has appeared at several Obama events this primary campaign season.

"Ted and I talked about me filling in for him at Wesleyan University earlier this week. Considering what he's done for me and for our country, there's nothing I wouldn't do for him. So I'm looking forward to standing in his place on Sunday even though I know I won't be able to fill his shoes," Senator Obama said Thursday.

Kennedy's ties to Wesleyan include his son, Edward Jr. , who graduated in 1983. Kennedy himself received an honorary doctorate from Wesleyan in 1984.