You probably saw this already but I believe the Christian, father of your Michael is buried at Salem Evangelical Lutheran Cemetery in Lititz PA. His tombstone shows he lived from 1827-1891. Name shown as Christian R Shank. First wife Mary Miller(?), second wife Catharine B. Might be harder to trace the family further back as censuses didnt include household members before 1850.
I looked for a Christian Shenk in Warwick Twp in 1850 born about 1827 but found none. The one born closest to 1827 I found in Manor Twp & he's single, with another family. Born 1828. Then I looked for his parents. There were only a couple families where the husband/father was born close to 1800. Both named Henry Shenk. One born 1791, the other 1800. The one living closest to where Christian was, was Henry, born 1800. The two residences were only a few numbers apart. I think this might be his family.
Parents Henry & Fanny Shenk. Siblings Michael, Elizabeth & Jacob. Christian wasnt in the household, but given the ages, he could've very well been the oldest. I dont know where Henry & Fanny are buried, but likely in Manor Twp somewhere. Or Conestoga Twp, since that's where they are in 1860.