Bruce Jenner has confessed his only concern is his children and is desperate not to hurt them as he undergoes gender reassignment surgery to become a woman. The former Olympian - who is currently undergoing gender reassignment surgery - has admitted his only concern during the transition will be his children Burt, 36, Casey, 34, Brandon, 33, Brody, 31, Kendall, 19 and Kylie, 17. The reality TV star - who also has four stepchildren, Rob, 28, Khloe, 30, Kourtney 36 and 34-year-old Kim from his marriage to his now estranged wife Kris Jenner - shared his worries in a new clip from his upcoming tell-all interview with Diane Sawyer, which will air on ABC on Friday April 24. In the snippet, Bruce says: ''I can't let myself hurt them. They're the only ones I'm concerned with.'' Although he appears to have no regrets about his decision, adding: ''It made me who I am.'' In previous clips released from the two-hour long show, entitled Bruce Jenner: The Interview, he is also heard telling Diane: ''My whole life has been getting ready for this.'' Jenner, 65, is said to be particularly concerned with the impact his decision to live as woman will have on his youngest daughters Kendall and Kylie. The Keeping Up With The Kardashians star was reported to have been spoiling them with gifts to prove his love to them and ensure his relationship with them doesn't change. A source said: ''He's constantly buying his girls gifts all of a sudden and everyone's worried that he's acting out or trying to buy affection. ''They are all trying to talk him into spending less, but he's doing things his way now.''..