A government MP has sought to reassure members of aviation pioneer Nancy-Bird Walton's family that the Department of Home Affairs has no intention of deporting them over confusion surrounding their citizenship status after one member of the family went into hiding.

Cathy Bird is the niece of the famous Australian pilot, and her father John Bird is a World War II veteran of the merchant marines. She and her siblings were born in Papua New Guinea to a Papuan mother before the nation achieved independence in 1975 and were granted Australian citizenship as children.

Cathy Bird, niece of Nancy-Bird Walton (inset) has gone into hiding after being told she is not an Australian citizen.

But, as the Herald reported on Thursday, when she and her sister sought to renew their passports two years ago, they were told they were not eligible as they were not citizens. Cathy Bird was granted a bridging visa that expired on October 31, before being renewed on Thursday after media inquiries.

She says she was told by a Border Force officer she could be detained and deported from her home in Cairns. She is now in an undisclosed location in NSW.