Good morning.
Actually the Shin  and Aleph are abbreviations for SHEM IMO...the name of his mother.
The letters after are an abbreviation for "She should live [and be well]" [Shetichye means she should live, the ,and be well is understood.] So while his father was deceased, his mother ws alive when he died.
Hope this helps.
Leya Aronson
Toronto Canada