Sayyiduna Abdullah bin Umar (may Allah be pleased with them both) said that the Messenger of Allah (peace and blessings be upon him) said: "None of you should sell over the sale of his brother, nor propose over (his) marriage proposal, unless he gives permission." And in the narration of Yahya: "unless he gives him permission."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب النكاح / 14033