Laura Bush and daughter Jenna appeared on CNN's Larry King Live Thursday.

(CNN) — President Bush was quick to endorse John McCain when the Arizona senator wrapped up his bid for the Republican presidential nomination.

But another Bush might not be so sure.

Speaking with CNN's Larry King Wednesday night, Jenna Bush said she hasn't decided yet who she will vote for in November.

"I don't know," Jenna Bush, daughter of President and Mrs. Bush, said when asked if she will back McCain.

"Of course [I am open]. I mean, who isn't open to learning about the candidates and I'm sure that everybody's like that," she added.

Though the younger Bush conceded she has "been too busy with books to really pay that much attention."

Meanwhile, mother Laura Bush was quick to affirm that she will be voting for the Republican candidate in the fall.

The two appeared on the show to discuss Jenna Bush's upcoming wedding next month.

"[It will be] outdoors, very small wedding, you 'know, very small, all relatives, our families, really, kind of big," Jenna Bush said. “So it's half-family and then half very close friends."