Separating from LO

Hi. Just a concern... Once I start work my LO will be staying with my mum from sun eve to fri eve as there is no one to take care of him at home and we do not want to put him at infant care or hire a nanny/maid. He will be 3.5months when i start work. Its impossible to pick him up and send him to my mums place everyday due to transportation and work timings... Will he forget me if I only spend two days with him? I’m very sad I can’t do anything about it..... any mummies in the same situation? ;(