Confused about dog’s behavior towards toddler

Hi! Hoping for some insight on my dog’s indifference towards my child. We rescued my 7 year old pup about 4 years ago & we have a 16 month old toddler. Dog has always been a bit anxious but mostly with separation situations or just in general skittishness. No matter the dog’s temperament, I am very conscious about keeping young children supervised and dogs in their own safe space away from the chaos. Especially because she’s very low energy & often retreats to her own space in the house. It’s been really easy to keep them separate until my toddler just started walking. I’m still careful about supervision and separation, but of course there are times he’s walking through the house and their paths cross.

My concern lies with not being able to read how my dog is feeling. I’ve tried to safely introduce them with me between them but the dog completely ignores him and maintains focus on me. Since he’s been born she kinda just acts like he’s not there. Doesn’t try to sniff, lick, or interact. It seems she is deliberately avoiding eye contact and physical interaction with toddler. What could this mean? Is it a warning that interaction with him makes her really nervous? or am I reading too much into it. Her tail is usually wagging and she’s acting normal towards me during the interaction. I want to not feel panic if there’s ever a time that toddler walks over to the dog because he’s definitely becoming increasingly more interested in her- rightfully so since she’s a part of the family! I’m just having trouble navigating it.