I am looking for a Hadith that testifies the keeping of dolls and other related materials are forbidden at home.

Praise be to Allah, the Lord of the World; and may His blessings and peace be upon our Prophet Muhammad and upon all his Family and Companions.

We do not know any Hadith that prohibits keeping dolls and the like for children in a house. Imam Nawawi said: 'Toys for girls are exempted from the ruling of prohibition of making the three dimensional pictures' . The evidence for this permission is the Hadith of Ayisha (Radiya Allahu Anhu) who said: "I had some friends and used to play with them, when the Prophet (Sallallahu Alaihi wa Sallam) enters in the house they would restrain from playing. The Prophet (Sallallahu Alaihi wa Sallam) brings them to me and then we play together" [Reported by Imams al-Bukhari and Muslim ].
Among the toys of Ayisha (Radiya Allahu Anhu) there was a horse with two wings, and she used to keep it in the house of the Prophet Muhammad (Sallallahu Alaihi wa Sallam).
However, it is dislikeable for a Muslim to keep such toys in the place of prayer to avoid any distraction. Other than the toys of children the pictures of living beings are forbidden as reported in many sound Ahadith. The Prophet (Sallallahu Alaihi wa Sallam) said: "The people who will receive the severest punishment (on the Day of Judgment) from Allah will be the picture makers" .
Allah knows best.