Is J'en lui envoye plausible?

Question

I have a related question to the "Je lui envoye une message vs Je l'envoye une message"
 As the something ( a message) is mentioned after the verb, you don't need to worry about it; it is just the someone,  which in this case is the indirect pronoun  'lui'. (i lifted this from the response to that question)
If it is already established that a message is being sent, can i say: j'en lui envoye ?

Céline Pickard · Accepted Answer

Bonjour Vivien,
In French, "je l'envoie un message" is not correct. You would always say or write:
Je lui envoie un message = I am sending him/her a message
Je lui en envoie un = I am sending him/her one
-> envoyer [quelque chose] à [quelqu'un]
Conjugate semir regular verbs in -oyer, -ayer, -uyer in Le Présent
Also, the pronoun "en" is needed here as in French the number cannot stand alone like in English:
Je lui en envoie un [message] = I am sending him/her one (of them)
J'en veux trois. = I want three of them.
Tu en as mangé dix ! = You ate ten of them!
 
I hope this is helpful.
Bonne journée !