From Egyptian Secrets of Albertus Magnus, Joseph H. Peterson edition:
For Marasmus of Children.
The child must be carried in the morning toward the rising sun, then speak: Be welcome in the name of God, thou sunshine, whence comest thou so mild, help me and my dear child. God the heavenly Father, pray, that my child help he may. Beseech the Holy Ghost, that by the heavenly host he may return the natural blood and flesh unto my child.
The grimoire Egyptian Secrets of Albertus Magnus lists this spell.