Nothing is sweeter to children than a mother; love your mother, children, for no where is there a love as sweet as this.

[οὐκ ἔστι μητρὸς οὐδὲν ἥδιον τέκνοις•
ἐρᾶτε μητρός, παῖδες, ὡς οὐκ ἔστ’ ἔρως
τοιοῦτος ἄλλος ὅστις ἡδίων ἐρᾶν.]

Euripides (485?-406? BC) Greek tragic dramatist

Erectheus [Ἐρεχθεύς], frag. 358 (TGF) (422 BC)
    (Source)

Ironically, Erechthus, as King of Athens, sacrifices one or more of the daughters to ensure the wartime survival of Athens.

Nauck frag. 358, Barnes frag. 35, Musgrave frag. 8. (Source (Greek)). Alternate translations:

There's no affection can exceed what children
Feel for their Mother; let this love, my Sons,
Deep in your tender bosoms be implanted:
For no attachments equal kindred ties.
[tr. Wodhull (1809)]

Children have nothing sweeter than their mother.
Love your mother children, there is no kind of love anywhere
Sweeter than this one to love.
[tr. @sentantiq (2015)]