I have dc 16, 13, 5, 5 and 3.
Between the eldest and the youngest 3, that I can think of,
Tv - no on demand, no streaming, no YouTube, dvds were only just getting popular when dd1 was born, music was on CD, charts were sales of singles. CBeebies was there, but only if you had sky (We didn't), so we had 4 channels (no c5 either where we lived then). Kids tv was on bbc2 for a couple of hours in the morning, and bbc1 for a couple of hours after school.
Pubs - kids were allowed and almost encouraged in during the day, my youngest 3 have never set foot in a pub.
Smoking was still allowed in public places.
Dd1 was weaned at 15 weeks, the younger 3 waited till 6 months. Dd1 was weaned traditionally too, no blw then.
Food - lots of things that are common place now weren't then (certainly not in your big standard asda anyway!) - avocados, hummus, organic food.
Internet - we had dial up, many people had no internet at all. There was little social media, forums were few and far between, and populated by "geeks" generally. No online shopping, although I was shopping online with Iceland by the time dd1 was 3. There wasn't the wealth of information out there that there is now.
Vaccinations - Andrew Wakefield was still very influential when dd1 was born.
Maternity leave - longer and more generous now.
Childcare - the 15/30 hours stuff wasn't there as much, dd1 got 15 hours once she turned 3.5, dd3 could have had 15 hours since she turned 3, and could have 30 hours after summer.
Benefits - when dd1 was born, tax credits were literal tax credits, her dad got a new tax code which gave him a tax refund and extra money each pay. Tax credits (as we know it now) came in April 2003, and was an absolute shambles for months - I think we were 8 months before we got a payment. There was no benefit cap, no bedroom tax, no limit on the number of children.