Heinz Sommerfeld was born in Berlin on March 26th, 1927. His mother was Fanny, born in 1898 in Kiel, his father was Max Sommerfeld, born in 1902 in Krojanke.
On January 5th, 1939, Heinz came to the Netherlands with a big Kindertransport. First he was housed in the Dommelhuis in Eindhoven; in November 1939 he was moved to the Burgerweeshuis in Amsterdam for a few days. At the end of November, 1939, he came in foster care with the Lipschits family in Maastricht (Muntstraat 4). He lived there until January 17th, 1941, when he moved to Utrecht, to the orphanage on the Nieuwe Gracht.
In February 1942 he was deported to Westerbork. On January 20th, 1944 he was put on the train to Theresienstadt, from where he was deported to Auschwitz on September 28th, 1944. According to the sources he was gassed upon arrival there. (https://www.holocaust.cz/en/database-of-victims/victim/151593-heinz-sommerfeld/)
His mother Fanny was deported from Berlin (Strassburgerstr. 15, Berlin N 54) to Riga on October 19th, 1942. She was killed in Riga on October 22nd, 1942.
Father Max was in Lodz in 1939. It is not known what his fate was.
See also: http://www.dokin.nl/deceased-children/heinz-sommerfeld-born-26-mar-1927?A=SearchResult&SearchID=2718889&ObjectID=4831207&ObjectType=35