Maddy Ralphean was the mother of Abigail Ralphean, the patient in Merry Little Christmas. She was portrayed by actress Meredith Eaton. Maddy had cartilage hair hyperplasia dwarfism and stood only 4'1" tall.
Maddy took her daughter, who also suffered from dwarfism, to Princeton-Plainsboro Teaching Hospital when she suffered a pneumothorax. Abigal received surgery to relieve the problem, but when Cuddy was examining her and reassuring Maddy that the problem was most likely not serious, Gregory House burst in to see Dr. Cuddy and instead both started a differential on Abigail and started making fun of Maddy's height. Maddy was upset that Dr. House was making an issue of her height, but Dr. House convinced her that he should be able to work on her daughter's case.
However, in order to get House to take a plea bargain, Cuddy took House off the case and cut off his Vicodin. Although Cuddy and Wilson worked with House's team, they just stumbled around and most of them looked back to House for clues. Maddy started to get worried and wondered where House was. Wilson lied and told her House was "sick".
However, House managed to steal some oxycodone off one of Wilson's dead patients and was back in fighting form. He finally theorized that Abigail wasn't really a dwarf - something was affecting her pituitary gland to keep it from producing human growth hormone. He traced it to Langerhans cell histiocytosis, a treatable condition.
The revelation that Abigail's height was a medical condition and not a hereditary problem meant that, unlike a true dwarf, she would respond to human growth hormone and grow to near average height. However, Abigail had grown used to the fact that she was small and wanted to stay that way. Maddy supported her decision. However, Dr. House called her aside and reminded Maddy that Abigail's short stature would mean that she would face severe problems with her life as the world was built with average size people in mind. He reminded her that what made both himself and her strong was the fact they were both freaks of nature, but that this comes at a cost. Abigail might get stronger because of her height, but House asked Maddy just how strong she wanted her daughter to be.
Maddy finally spoke to Abigail and convinced her to take human growth hormone.