Looking for Mills of Pennsylvania My Father Told US That His Mills Line Came from Wales but I Have Not Found the Person Who Emigrated from Another...

Hello, my name is Sue, looking for my MILLS ancestors who were from the southeastern corner of Pennsylvania. Mostly born in Delaware, Chester and Philadelphia Counties. I'm looking for the person who emigrated from another country. According to family lore, that person may have been Welsh. When William Penn came to Pennsylvania in 1681 he had been given 40,000 acres by the King of England. William Penn had recently become a Quaker and believed in freedom of religion and other freedoms which he couldn't find in Europe. He welcomed the Welsh people, some of which were Society of Friends(Quakers) and also Welsh Baptists. They thought that they would have their own "barony" where they could worship their own religion, speak their own language and keep their own culture. Later, it didn't work out that way but they became very industrious and part of the framework of the new towns and cities there in that region. I have found that another branch of the family, HORNE were Quakers.
My family member were mostly farmers, milkmen, cobblers and hatters. Then later the men were delivery men and interior decorators for the wealthy families on the Philadelphia Main Line. Some were horsemen who raised thoroughbreds for racing and horse shows.