Lewis Phillips appears in over 20 court documents in White County (TN) between 1815 and 1840.  He apparently surveyed and constructed roads for the county and was a frequent member of juries. 

Here is perhaps the most surprising entry, dated July 3, 1837.
“ Issued on the humble petition of Lewis Phillips he is permitted to keep a tavern house of public entertainment in White County and thereupon entered into and acknowledged bond in the sum of two thousand dollars with Jabez G. Mitchell his security conditioned as the law requires.”

1850: Census, Desoto, Mississippi; Roll: M432_371; Page: 33; Enumerated: 27 Sep 1850

Dwelling#323 Family#323 (Lines 21 - 24)
Lewis Phillips 60 c1790 VA Occ Farming RE=$2000
Margaret Phillips 60 c1790 VA
James D Phillips 21 c1829 TN Occ Farming
Crockett H Phillips 19 c1831 TN Occ Farming

Caution should be used in assuming that James D and Crockett H are sons of Lewis and Margaret because this census doesn't specify relationships -but it makes sense that Lewis and Margaret are the parents of James and Crockett.

Also on this page (with one household in between);

Dwelling#321 Family#321 (Lines 10-15)
John S Phillips 31 c1819 TN Occ Farming RE=$500
Phebe Phillips 31 c1819 TN
James L Phillips 10 c1840 TN
Joseph C Phillips 3 c1847 MS
John A Phillips 1 c1849 MS
James Woods 20 c1830 TN Occ Farming

It is possible that John S. Phillips listed here is a son of Lewis and Margaret.

1860 Census: Desoto, Mississippi; Roll: M653_581; Page: 102; Post Office: Greenleaf.; Enumerated: 29 Aug 1860

Dwelling#748 Family#748 (Lines 30 - 33)
Lewis Phillips 70 c1790 VA Occ Farmer RE=$4000 PP=$21,000
Margaret Phillips 70 c1790 VA
Elizabeth O Nelson 34 c1826 TN
A A Nelson 5 c1855 MS

NOTEs: Who is Elizabeth Nelson? A widowed daughter of Lewis and Elizabeth? Marital status is not given in this census (nor relationship)..

J S Phillips and wife Phoebe are right above Lewis and Margaret (Dwelling/Family #747) and right below Lewis is a Mary P Phillips (Dwelling/Family #749) who appears to be the head of a family that includes no male spouse so she may be a widowed daughter-in-law of Lewis. Perhaps one of Lewis and Margaret's sons was killed in the Civil War?

Also J D (James D) Phillips on this page (Dwelling/Family #745) apparently James D has married and now has offspring; it rather looks as though James may have married a woman who was previously married as there is s child in the household age 12 who has a surname of GRAY and both this child and James' wife were born in North Carolina.

Mississippi Marriages, 1776-1935
Name: Elizabeth Phillips
Spouse: Joseph B. Nelson
Marriage Date: 13 Feb 1850
County: Desoto

NOTEs: This looks like a good candidate for the husband of Elizabeth PHILLIPS.

1850 Census, Desoto, MS; Roll: M432_371; Page: 365; Enumerated: 15 Nov 1850

Dwelling#748 Family#748 (Lines 21 - 22)
Jos B Nelson 21 c1829 AL Occ Farming
Elizabeth Nelson 21 c1829 TN

Lewis PHILLIPS was listed on the White County, TN census in 1820. By 1875 a Chancery Court case in Tate County, MS. involved his heirs which include the heirs of A.W. MILLER whose wife Nancy was a daughter of Lewis PHILLIPS. The heirs listed were:
Margaret J. NEWBERRY,
W.L. MILLER,
J.C. MILLER,
Sarah E. BELL, (wife of J.W. Bell ),
All residents of Tate County, MS except for the Bells who lived in DeSoto CountyMS...all children of Nancy,deceased daughter of Lewis Phillips.

Next were the children of W. H. PHILLIPS, son of Lewis: Sophie SHAW ( wife of H.W. Shaw ).
Mary E. PHILLIPS,
Margaret STEWART ( wife of W. J. Stewart ),
Kindness JONES ( wife of A. T. Jones ) and
Harriet HARRISON ( wife of Henry Harrison )..all residents of Tate County, MS,
All children of W.H. PHILLIPS, deceased son of said Lewis.

Next were children of John S. PHILLIPS, deceased son of Lewis: Joseph PHILLIPS,
Elizabeth BRITTON ( wife of Lucius Britton)
A. J. PHILLIPS...All of Tate County,MS.

Next were other children of Lewis Phillips who were residents of Tate County, MS :
Tabitha MILLER (wife of W.S. Miller),
Elizabeth NELSON, widow, C.H.PHILLIPS.

William PHILLIPS, a minor, son of JOHN S. PHILLIPS deceased, (a son of Lewis Phillips aforesaid), who resided with his mother Phoebe PHILLIPS in Tate County, MS and Robert PHILLIPS and William PHILLIPS, minor children of J. PHILLIPS, deceased, who was a son of said Lewis, resident with their mother Margaret PHILLIPS in DeSoto County, MS.