After arriving at Stansted and taking the Stansted Express into Liverpool Street, enjoy a relaxed stroll through Spitalfields Market for a light coffee and browsing vintage stalls, then wander across to the atmospheric Leadenhall Market to admire the Victorian roof and maybe stop for a pastry. From there, take a gentle, mostly flat walk to the river and enjoy riverside views at Tower Hill / Tower of London (outside the grounds) before sitting for a short riverside break at St Katharine Docks to rest and watch the boats-perfect for pacing with an 80-year-old and a young teen while keeping to an easy schedule before hotel check-in.
After a riverside break, amble over to the charming green of St James's Park for a relaxed stroll and bird-watching-there are plenty of benches and gentle paths perfect for your mother and son. From there, take a short hop to the iconic view point at The Mall / Buckingham Palace to watch the palace façades and maybe catch guards on parade (timing permitting), then enjoy a comforting afternoon tea or light lunch at the nearby, cosy Clarence Pub or a café on Victoria Street before heading to the Royal National Hotel to check in at 2pm.
As the afternoon checks in and you've settled at the Royal National, enjoy a gentle, nearby evening by strolling to Russell Square for a peaceful sit-down among winter hollies, then cross to the bookish charm of The British Museum's exterior (stay in the courtyard area rather than full touring to keep it easy). Finish with a relaxed family dinner at the short walk-away Bloomsbury Bistro or an early table at Australian-themed restaurant Bill's on lively Great Russell Street - both offer comfortable seating, varied menus for your son, and easy access back to the hotel.
Start gently with a leisurely breakfast at Dishoom King's Cross (comfortable seating and kid-friendly options), then take a short, flat stroll to the nearby leafy Regent's Canal for a peaceful waterside walk - you can watch narrowboats glide by and sit on benches while your mother rests. Continue to the charming, compact Camden Lock Market for relaxed browsing of independent stalls and street food (plenty of seating areas and fun treats for your son), finishing with a calm riverside coffee at Mosaic at Stables Market before heading back to the Royal National to collect luggage later in the afternoon.
After a gentle morning, head for the leafy charm of Greenwich Park where you can sit on benches overlooking the Thames and enjoy panoramic views toward the City-there's a gentle path to the Royal Observatory (photo opportunity at the Prime Meridian line) and plenty of spots to rest. Wander down to the nearby Greenwich Market for casual browsing of crafts and tasty street-food snacks your son will enjoy, then take a short, flat riverside stroll toward Cutty Sark to admire the historic tea clipper from the outside before catching a relaxed Thames clipper or river taxi back toward central pick-up points for your transfer to Stansted.
As the afternoon winds down, take a short taxi or bus to Covent Garden for gentle street performers, craft stalls and an easy sit-down by the central market square-there are plenty of benches and cafés ideal for your mother and son. Follow this with a calm, early evening riverfront stroll along the quieter stretch near Southbank (around the Oxo Tower area) where you can enjoy views of the city lights, grab a casual riverside meal at Gabriel's Wharf cafés, and then return to the Royal National in good time to collect luggage and head to Stansted.