I can tell you a little about the Mollman/Moelman family.

IGI Marienthal Rees,Germany Film # 907578 and 907577 for Sankt Remigius Kirche in Borken, which is where Marienthal is located.

Johan Moelman married Aug 10, 1826 Marienthal Rees to
Mechteld Rathring Johan was 27, Mechteld was 20

Johan b.Jan 3, 1827
a second Johan was born Dec 17, 1827, one or the other died. It was custom for them to name a second child after one that had died.
Gertrud b.May 23, 1831
Hendrina b.Mar 4, 1833, also here a second child same name born June 25, 1837
Johanna b.Nov 13, 1834
Catherine is not in the IGI church index, but it may be that the film for her was not indexed, but is probably available.
Theodore b. Feb 19 1842 also is not in the IGI church index, but someone from the LDS church has submitted his information, which may or may not be correct. But is probably availble on microfilm.

1850 Census for Burlington, Racine, Wisconsin
I think I found the Moelman/Mollman family in the 1850 census in Burlington. the list below is from the census, and I have added who they married.

The name is spelled Marman
John 25 married Eliz Merrick
Gertrud 22 married Joseph Merrick
Catherine 10 married Bernard Marick
Theodore 8 married Helen Rademacher, Catherine Lensing
Genett 18...think this one is Hendrina married William Baumgartner.
Johanna was not listed with them she could of been a servent in somebody's house. She would of been about 15. She married Herman Lensing.

also a death record in 1848 for John Moelman age 51 who was probably their father.

The Merricks listed above are brothers and sisters.