Imogen did not know about the wedding before starting BB

The former Miss Wales had not even been aware brother Owain, 26, was marrying.

The ceremony has been arranged in the past seven weeks, since Imogen moved into Channel Four's Big Brother house.

Her father Charles Thomas said: "It's unfortunate that everything has clashed really." The family plan a second wedding celebration when Imogen leaves.

Mr Thomas said he had watched Friday evening's TV double eviction, for which Imogen had been nominated, and was pleased she had come through it.

He said: "It's a double celebration really isn't it, because Imogen has survived yet another eviction night and I think that people can see her in the light that she should be seen in, so I'm really chuffed today."

Imogen, from Llanelli, is a bar hostess who was Miss Wales in 2003, and has a BSc degree in health studies and psychology. She speaks fluent Welsh, has a fear of spiders and loves to kick-box.

Mr Thomas said: "It's been arranged in about seven weeks so Imogen knew nothing at all about it, otherwise she wouldn't have taken part [in Big Brother].

"It's unfortunate that everything has clashed really.

"I'm sure that we'll arrange some kind of celebration with Owain and Donna and Imogen when she does come out.