15 month old not walking

My baby girl has been crawling and cruising And climbing for months and walks with her push walker, but still won’t try and walk on her own. If we try and take her hand she sits, if we try taking both hands she just lifts her legs, if we hold her by the waist she just again lifts her legs. She is 15 month and developing at all the correct milestones and actually in front on a many with the exception of walking. Can anyone offer any hints as to how we can help encourage her to walk with our hands. Thanks