cosus tristissimus, reliquil septem, infantulos

Are you sure about the first and third words? It might help to know the date of the text.

tristissimus 'very sad'
septem 'seven'
infantulos 'small children'
is there a line (macron or tilde) over the 'o' in cosus?
Is the final letter in reliquil really an 'l' or perhaps a 't'. Are the commas really there in the original?

Ceci n'est pas un seing.