Janssen-Muller in Emden,de

My grandmother Antje Janssen and grandfather Haye Muller were born in Emden, Germany, which I understand is in Friesland.Can find nothing on either of these two.He passed away in Emden and she with her two sons Herbert and Haye came to the USA in 1884. Have not been able to find their passage.Do these name sound familiar to anyone.